cmd/bosun: specify time format in elastic queries
cmd/bosun: specify time format in elastic queries

This makes it so queries still work regardless of the particular datetime mapping in elastic
bookingcom/bosun,bookingcom/bosun,bosun-monitor/bosun,mhenderson-so/bosun,bosun-monitor/bosun,simnv/bosun,mhenderson-so/bosun,csmith-palantir/bosun,simnv/bosun,alienth/bosun,bookingcom/bosun,leapar/bosun,seekingalpha/bosun,seekingalpha/bosun,mhenderson-so/bosun,leapar/bosun,simnv/bosun,alienth/bosun,csmith-palantir/bosun,simnv/bosun,csmith-palantir/bosun,bookingcom/bosun,bosun-monitor/bosun,mhenderson-so/bosun,alienth/bosun,bookingcom/bosun,bosun-monitor/bosun,alienth/bosun,simnv/bosun,seekingalpha/bosun,leapar/bosun,bosun-monitor/bosun,bookingcom/bosun,seekingalpha/bosun,csmith-palantir/bosun,csmith-palantir/bosun,alienth/bosun,leapar/bosun,mhenderson-so/bosun,simnv/bosun,seekingalpha/bosun,leapar/bosun,mhenderson-so/bosun,seekingalpha/bosun,leapar/bosun,bosun-monitor/bosun,alienth/bosun,csmith-palantir/bosun